Marketable Securities - Maturities of Debt Securities Classified as Available-for-Sale (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Jun. 30, 2015
Marketable Securities [Abstract]
Fair Value, Due within one year	$ 44,385	$ 46,516
Fair Value, Due after one year through five years	5,985	39,650
Fair Value	50,370	86,166
Net Carrying Amount, Due within one year	44,622	46,646
Net Carrying Amount, Due after one year through five years	6,015	39,831
Net Carrying Amount	$ 50,637	$ 86,477